2,2,2-trifluoroethyl butanoate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g of 17α,21-dihydroxy-pregna-4-ene-3,20-dione and 10 ml of trifluoroethyl butanoate in 50 ml of methyl ethyl ketone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding at regular time intervals 1 g of lipase. After completion of the reaction, the lipase was filtered off, the filtrate was concentrated under vacuum, taking up the residue three times with solvent. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The richer fraction was evaporated to obtain 0.89 g (2.14 mM) of 17α-hydroxy-21-butanoyl-pregna-4-ene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding at regular time intervals 1 g of lipase After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The richer fraction was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g of 17α,21-dihydroxy-pregna-4-ene-3,20-dione and 10 ml of trifluoroethyl butanoate in 50 ml of methyl ethyl ketone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding at regular time intervals 1 g of lipase. After completion of the reaction, the lipase was filtered off, the filtrate was concentrated under vacuum, taking up the residue three times with solvent. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The richer fraction was evaporated to obtain 0.89 g (2.14 mM) of 17α-hydroxy-21-butanoyl-pregna-4-ene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding at regular time intervals 1 g of lipase After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The richer fraction was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g of 17α,21-dihydroxy-pregna-4-ene-3,20-dione and 10 ml of trifluoroethyl butanoate in 50 ml of methyl ethyl ketone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding at regular time intervals 1 g of lipase. After completion of the reaction, the lipase was filtered off, the filtrate was concentrated under vacuum, taking up the residue three times with solvent. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The richer fraction was evaporated to obtain 0.89 g (2.14 mM) of 17α-hydroxy-21-butanoyloxy-pregna-4-ene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding at regular time intervals 1 g of lipase After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The richer fraction was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g (2.879 mM) of 17α,21-dihydroxy-pregna-4,9(11)-diene-3,20-dione and 10 ml of trifluoroethyl butanoate in 100 ml of acetone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding 1 g of lipase at regular time intervals. After completion of the reaction, the lipase was filtered off and the filtrate was concentrated under vacuum, taking up the residue three times with acetone. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The less polar components were removed, to obtain the richer fraction which was evaporated to yield 0.95 g (2.29 mM) of 17α-hydroxy-21-butanoyloxy-pregna-4,9(11)-diene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding 1 g of lipase at regular time intervals After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The less polar components were removed to obtain the richer fraction which was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g (2.879 mM) of 17α,21-dihydroxy-pregna-4,9(11)-diene-3,20-dione and 10 ml of trifluoroethyl butanoate in 100 ml of acetone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding 1 g of lipase at regular time intervals. After completion of the reaction, the lipase was filtered off and the filtrate was concentrated under vacuum, taking up the residue three times with acetone. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The less polar components were removed, to obtain the richer fraction which was evaporated to yield 0.95 g (2.29 mM) of 17α-hydroxy-21-butanoyloxy-pregna-4,9(11)-diene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding 1 g of lipase at regular time intervals After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The less polar components were removed to obtain the richer fraction which was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g of 17α,21-dihydroxy-pregna-4-ene-3,20-dione and 10 ml of trifluoroethyl butanoate in 50 ml of methyl ethyl ketone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding at regular time intervals 1 g of lipase. After completion of the reaction, the lipase was filtered off, the filtrate was concentrated under vacuum, taking up the residue three times with solvent. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The richer fraction was evaporated to obtain 0.89 g (2.14 mM) of 17α-hydroxy-21-butanoyloxy-pregna-4-ene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding at regular time intervals 1 g of lipase After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The richer fraction was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g (2.879 mM) of 17α,21-dihydroxy-pregna-4,9(11)-diene-3,20-dione and 10 ml of trifluoroethyl butanoate in 100 ml of acetone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding 1 g of lipase at regular time intervals. After completion of the reaction, the lipase was filtered off and the filtrate was concentrated under vacuum, taking up the residue three times with acetone. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The less polar components were removed, to obtain the richer fraction which was evaporated to yield 0.95 g (2.29 mM) of 17α-hydroxy-21-butanoyloxy-pregna-4,9(11)-diene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding 1 g of lipase at regular time intervals After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The less polar components were removed to obtain the richer fraction which was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g of 17α,21-dihydroxy-pregna-4-ene-3,20-dione and 10 ml of trifluoroethyl butanoate in 50 ml of methyl ethyl ketone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding at regular time intervals 1 g of lipase. After completion of the reaction, the lipase was filtered off, the filtrate was concentrated under vacuum, taking up the residue three times with solvent. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The richer fraction was evaporated to obtain 0.89 g (2.14 mM) of 17α-hydroxy-21-butanoyl-pregna-4-ene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding at regular time intervals 1 g of lipase After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The richer fraction was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g of 17α,21-dihydroxy-pregna-4-ene-3,20-dione and 10 ml of trifluoroethyl butanoate in 50 ml of methyl ethyl ketone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding at regular time intervals 1 g of lipase. After completion of the reaction, the lipase was filtered off, the filtrate was concentrated under vacuum, taking up the residue three times with solvent. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The richer fraction was evaporated to obtain 0.89 g (2.14 mM) of 17α-hydroxy-21-butanoyloxy-pregna-4-ene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding at regular time intervals 1 g of lipase After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The richer fraction was evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1 g (2.879 mM) of 17α,21-dihydroxy-pregna-4,9(11)-diene-3,20-dione and 10 ml of trifluoroethyl butanoate in 100 ml of acetone was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours, adding 1 g of lipase at regular time intervals. After completion of the reaction, the lipase was filtered off and the filtrate was concentrated under vacuum, taking up the residue three times with acetone. The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture. The less polar components were removed, to obtain the richer fraction which was evaporated to yield 0.95 g (2.29 mM) of 17α-hydroxy-21-butanoyloxy-pregna-4,9(11)-diene-3,20-dione. was reacted at 45° C. in the presence of 5 g of Candida cylindracea lipase for 8-10 hours adding 1 g of lipase at regular time intervals After completion of the reaction the lipase was filtered off the filtrate was concentrated under vacuum The semi-solid residue was purified by chromatography on a silica gel column with a dichloromethane/methanol 99:1 mixture The less polar components were removed to obtain the richer fraction which was evaporated